Marine survey systems are used to acquire data (e.g., seismic, electromagnetic) regarding Earth formations below a body of water such as a lake or ocean. The marine survey systems typically use a plurality of sensor streamers which contain one or more sensors disposed proximate an outer jacket.
In some situations, one or more sensor streamers may be disconnected from the survey system, the disconnection possibly caused by failure of a coupling mechanism or in some situations the sensor streamer may be severed (e.g., by the propeller of a passing vessel). In some failure scenarios, particularly with sensor streamers filled with alcohol or oil, the sensor streamer becomes negatively buoyant, thus tending to sink. In order to avoid complete loss of the sensor streamer, an inflatable lifting bag system may trigger (i.e., a retriever system), which causes the sensor streamer to surface.
Retriever systems available prior to the current disclosure are large in relation to the size of the sensor streamers. The size makes the retriever systems heavy, creates significant drag, and causes significant turbulence in the water near the sensor streamers. Moreover, each retriever system may be an anchor-point for marine growth, such as barnacles. For example, it is currently believed that marine growth preferentially occurs on irregular external streamer surfaces, possibly due to micro-turbulence at such external surface irregularities during towing operations.